Internet Engineering Task Force (IETF) A. Durand
Request for Comments: 6302 Juniper Networks
BCP: 162 I. Gashinsky
Category: Best Current Practice Yahoo! Inc.
ISSN: 2070-1721 D. Lee
Facebook, Inc.
S. Sheppard
ATT Labs
June 2011
Logging Recommendations for Internet-Facing Servers
Abstract
In the wake of IPv4 exhaustion and deployment of IP address sharing
techniques, this document recommends that Internet-facing servers log
port number and accurate timestamps in addition to the incoming IP
address.
Status of This Memo
This memo documents an Internet Best Current Practice.
This document is a product of the Internet Engineering Task Force
(IETF). It represents the consensus of the IETF community. It has
received public review and has been approved for publication by the
Internet Engineering Steering Group (IESG). Further information on
BCPs is available in Section 2 of RFC 5741.
Information about the current status of this document, any errata,
and how to provide feedback on it may be obtained at
http://www.rfc-editor.org/info/rfc6302.
Copyright Notice
Copyright (c) 2011 IETF Trust and the persons identified as the
document authors. All rights reserved.
This document is subject to BCP 78 and the IETF Trust's Legal
Provisions Relating to IETF Documents
(http://trustee.ietf.org/license-info) in effect on the date of
publication of this document. Please review these documents
carefully, as they describe your rights and restrictions with respect
to this document. Code Components extracted from this document must
include Simplified BSD License text as described in Section 4.e of
the Trust Legal Provisions and are provided without warranty as
described in the Simplified BSD License.
Durand, et al. Best Current Practice [Page 1]RFC 6302 Internet-Facing Server Logging June 2011Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Recommendations . . . . . . . . . . . . . . . . . . . . . . . . 3
3. ISP Considerations . . . . . . . . . . . . . . . . . . . . . . 4
4. Security Considerations . . . . . . . . . . . . . . . . . . . . 4
5. References . . . . . . . . . . . . . . . . . . . . . . . . . . 4
5.1. Normative references . . . . . . . . . . . . . . . . . . . 4
5.2. Informative references . . . . . . . . . . . . . . . . . . 4
1. Introduction
The global IPv4 address free pool at IANA was exhausted in February
2011. Service providers will now have a hard time finding enough
IPv4 global addresses to sustain product and subscriber growth. Due
to the huge existing global infrastructure, both hardware and
software, vendors, and service providers must continue to support
IPv4 technologies for the foreseeable future. As legacy applications
and hardware are retired, the reliance on IPv4 will diminish;
however, this is a process that will take years, perhaps decades.
To maintain legacy IPv4 address support, service providers will have
little choice but to share IPv4 global addresses among multiple
customers. Techniques to do so are outside of the scope of this
document. All include some form of address translation/address
sharing, being NAT44 [RFC3022], NAT64 [RFC6146] or DS-Lite [DS-LITE].
The effects on the Internet of the introduction of those address
sharing techniques have been documented in [RFC6269].
Address sharing techniques come with their own logging infrastructure
to track the relation between which original IP address and source
port(s) were associated with which user and external IPv4 address at
any given point in time. In the past, to support abuse mitigation or
public safety requests, the knowledge of the external global IP
address was enough to identify a subscriber of interest. With
address sharing technologies, only providing information about the
external public address associated with a session to a service
provider is no longer sufficient information to unambiguously
identify customers.
Note: This document provides recommendations for Internet-facing
servers logging incoming connections. It does not provide any
recommendations about logging on carrier-grade NAT or other address
sharing tools.